The present invention relates to an apparatus for stacking sheet-like products delivered one after another in a spaced relationship to each other with a transporting device, which apparatus includes a conveyor for conveying the sheet-like products toward a stacking position and a braking arrangement. Generally, the speed of the conveyor corresponds to the speed of the transporting device.
Such an apparatus is used, for example, with a sheet metal drier to insure its continuous operation. The metal sheets, which leave the drier, e.g., lacquered metal sheets, are delivered one after another by a transporting device to a stacker with a very high speed of about 6,000-10,000 sheets per hour. However, braking of the sheets during their deposition onto a piling table is rather difficult. With sudden braking, the sheets can be damaged. Further, stacking is complicated by the back pressure applied by buffer or resilient stop elements generally provided at the end of the piling table.
It was suggested already to decelerate the sheet-like products before they reach their stacking position or the piling table. To prevent a collision of a following sheet with the braked sheet, it was suggested to provide for overlapping or slat feeding of sheets during sheet braking. Such an apparatus is described in German application P43 14 760 7 of the assignee of the present application. In this apparatus, the conveyor is formed as a conveyor belt, and the braking device is arranged downstream of the conveyor in the transporting direction and beneath the transporting plane of the conveyor. After the rear edge of a sheet leaves the conveyor, it is deposited on the braking device and is decelerated thereby. During the deceleration, the front edge of the following non-decelerated sheet overlaps the rear edge of the decelerating sheet. The decelerated sheet is conveyed with a reduced speed to the piling table and is deposited thereon.
However, during the deposition of the sheets, they or already stacked sheets can be easily damaged. Thus, the front edge of the following sheet can damage the surface of the preceding decelerated sheet when it impacts the same and is pushed therealong.
Accordingly, a main object of the invention is a stacking apparatus which would insure damage-free stacking of sheet-like products delivered at high speed.